[ACCEPTED]-Instantiating anonymous object using C# object initializer syntax stored in string-dynamic
Anonymous classes are C# syntactic sugar (see Remarks section here). csc.exe creates 12 a class with private fields and a read/write 11 property with the type inferred from context. All 10 uses of the object are, again, inferred.
What 9 this means is you cannot create an anonymous 8 class at run time because the CLR sees them 7 no differently than any other class (again, because 6 it is C# syntactic sugar).
So instead:
- Use a
Dictionary<string,object> - Use JSON.NET, XML or something like it that has some already-defined scheme for parsing a string to get an object. This requires the properties be well-defined, however.
- Use
System.Reflection.Emitto create the type at run-time, but I see no real benefit to this over just aDictionary<string,object>
I also 5 have concerns of what you're doing because 4 this as a string very likely means to me 3 that you are accepting user input of some 2 kind. Be wary of the security issues in 1 whatever you do.
It's not possible using anonymous types, however 2 you can do it with Reflection Emit using 1 the TypeBuilder class, specifically TypeBuilder.Create(..).
http://msdn.microsoft.com/en-us/library/system.reflection.emit.typebuilder.createtype.aspx
The best way to do it is to use serialization. But 11 of course, that doesn't use the same string 10 format that you described.
Your object initializer 9 does not have to contain constant values.
string myName="bob";
int myAge=30;
double mySalary=100000;
object empData = new { name = myName, age = myAge, salary = mySalary };
So 8 in your scenario you would have to parse 7 out the individual elements from your string, and 6 perform some conversions on them to coerce 5 them into the types you want.
If you are 4 not married to this particular string format, you 3 can serialize and deserialize your objects 2 and accomplish the same thing using XML 1 much more easily.
There's no direct easy way to do so. Basically, you 7 have these options:
- Parse the string manually.
- Use the C# compiler to compile that object as a part of an assembly and use reflection to figure out the contents.
- (not sure if it's possible, C# 4.0 only): Use C# 4.0 managed compiler classes to parse the expression and infer the stuff.
None of which is ideal 6 in my opinion. I'd consider QueryString 5 like pairs, XML or JSON or some other format 4 that has parsers available out there instead 3 if you have the option and consider storing 2 data in a dictionary instance instead of 1 creating an object for every expression.
I don't think this question answers yours 11 per se, but it will tell you why it's not 10 possible to create anonymous instances of 9 objects using strings in a manner such as 8 you suggest:
How do I create and access a new instance of an Anonymous Class passed as a parameter in C#?
Anonymous types don't have any 7 public fields, consequently while you can 6 do this for a named object, it's not so 5 simple to do it for an anonymous type. That 4 said, there's nothing to stop you [as suggested 3 by BFree] using reflection to emit the MSIL 2 for the anonymous type - which isn't exactly 1 straightforward, but isn't impossible either.
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